title: [The fate of intravenously-administered sugar as energy source (author's transl)].
abstract: 10 micromoles of 14C-U-labelled maltose, glucose, fructose and galactose were injected intravenously into rats and it was found that more than 10% was exhaled as CO2 within 60 minutes and about 50% within 24 hours. Anaesthesia lowers the values by one third. The main amount of 14C is found in the liver. By comparison, only 0.24% and 0.17% were metabolized to CO2 within 60 minutes from sucrose and lactose respectively, whilst within 24 hours the equivalent figures were 2% and 3%. This small turnover persists after removal of the gut, as was demonstrated by an additional series of 1-hour experiments and is judged to signify parenteral hydrolysis of sucrose and lactose molecules. For both disaccharides the 1-hour renal excretion ranges from 66% to almost 100% compared with a range of 1.2% to 4.3% for glucose, maltose, fructose and galactose. Using 3-O-methylglucose, only 0.025% of the dose was exhaled as CO2 within 60 minutes, a quantity small enough to be due to contamination of the sample. Apart from glucose and fructose, maltose is considered to be useful for parenteral nutrition.
mesh_terms: D000818:Animals; D004734:Energy Metabolism; D005260:Female; D005632:Fructose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D007275:Injections, Intravenous; D008099:Liver / Q000378:metabolism; D008320:Maltose / Q000378:metabolism; D010288:Parenteral Nutrition; D011134:Polysaccharides / Q000008:administration & dosage / Q000378:metabolism*; D051381:Rats; D012119:Respiration
chemical_list: D011134:Polysaccharides; D005632:Fructose; D008320:Maltose; D005947:Glucose
vernacular_title: Das Schicksal intravenös als Energieträger verabreichter Zucker.